Determination and optimization of N-nitrosamines in salted fish by gas chromatography-mass spectrometry

We determined N-nitrosamines in salted fish by gas chromatography-mass spectrometry (GC-MS), optimized the sample preparation conditions, compared the response intensity of N-nitrosamines by SPME and dichloromethane ultrasonic extraction, and explored the impact of organic solvent, extraction time, extraction times on the determination. By ion selective electrode method, we determined the content of N-dimethylnitrosamine, N-diethylnitrosamine, N-nitroso-pyrrolidine and N-nitrosamines. Results show that the linear correlation coefficient is 0.999 2, 0.999 1, 0.999 1 and 0.999 2, with a linear range of 0~10 gmL-1. The method has good reproducibility (RSD2.1%, blank spiked recovery is 70%~80%) and high sensitivity (detection limit is 0.038 6 gkg-1, 0.022 7 gkg-1, 0.031 6 gkg-1 and 0.047 8 gkg-1,respectively).